Penicillins are used to treat infections caused by bacteria. They work by killing the bacteria or preventing their growth.

There are several different kinds of penicillins. Each is used to treat different kinds of infections. One kind of penicillin usually may not be used in place of another. In addition, penicillins are used to treat bacterial infections in many different parts of the body. They are sometimes given with other antibacterial medicines (antibiotics). Some of the penicillins may also be used for other problems as determined by your doctor. However, none of the penicillins will work for colds, flu, or other virus infections.

Penicillins are available only with your doctor's prescription, in the following dosage forms:

Oral

Amoxicillin

Capsules (U.S. and Canada)

Oral suspension (U.S. and Canada)

Tablets (U.S.)

Chewable tablets (U.S. and Canada)

Ampicillin

Capsules (U.S. and Canada)

Oral suspension (U.S. and Canada)

Bacampicillin

Oral suspension (U.S.)

Tablets (U.S. and Canada)

Carbenicillin

Tablets (U.S. and Canada)

Cloxacillin

Capsules (U.S. and Canada)

Oral solution (U.S. and Canada)

Dicloxacillin

Capsules (U.S.)

Oral suspension (U.S.)

Flucloxacillin

Capsules (Canada)

Oral suspension (Canada)

Nafcillin

Capsules (U.S.)

Tablets (U.S.)

Oxacillin

Capsules (U.S.)

Oral solution (U.S.)

Penicillin G Benzathine

Oral suspension (Canada)

Penicillin G Potassium

Oral solution (U.S.)

Tablets (U.S. and Canada)

Penicillin V Benzathine

Oral suspension (Canada)

Penicillin V Potassium

Oral solution (U.S. and Canada)

Tablets (U.S. and Canada)

Pivampicillin

Oral suspension (Canada)

Tablets (Canada)

Pivmecillinam

Tablets (Canada)

Parenteral

Ampicillin

Injection (U.S. and Canada)

Carbenicillin

Injection (U.S. and Canada)

Cloxacillin

Injection (Canada)

Methicillin

Injection (U.S.)

Mezlocillin

Injection (U.S.)

Nafcillin

Injection (U.S. and Canada)

Oxacillin

Injection (U.S.)

Penicillin G Benzathine

Injection (U.S. and Canada)

Penicillin G Potassium

Injection (U.S. and Canada)

Penicillin G Procaine

Injection (U.S. and Canada)

Penicillin G Sodium

Injection (U.S. and Canada)

Piperacillin

Injection (U.S. and Canada)

Ticarcillin

Injection (U.S. and Canada)

Before Using This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For penicillins, the following should be considered:

AllergiesÃ¢â�¬â€�Tell your doctor if you have ever had any unusual or allergic reaction to any of the penicillins or cephalosporins. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes, or procaine (e.g., Novocain) or other ester-type anesthetics (medicines that cause numbing) if you are receiving penicillin G procaine.

DietÃ¢â�¬â€�Make certain your health care professional knows if you are on a low-sodium (low-salt) diet. Some of these medicines contain enough sodium to cause problems in some people.

PregnancyÃ¢â�¬â€�Penicillins have not been studied in pregnant women. However, penicillins have been widely used in pregnant women and have not been shown to cause birth defects or other problems in animal studies.

Breast-feedingÃ¢â�¬â€�Penicillins pass into the breast milk. Even though only small amounts may pass into breast milk, allergic reactions, diarrhea, fungus infections, and skin rash may occur in nursing babies.

ChildrenÃ¢â�¬â€�Many penicillins have been used in children and, in effective doses, are not expected to cause different side effects or problems in children than they do in adults.

Some strengths of the chewable tablets of amoxicillin contain aspartame, which is changed by the body to phenylalanine, a substance that is harmful to patients with phenylketonuria.

Older adultsÃ¢â�¬â€�Penicillins have been used in the elderly and have not been shown to cause different side effects or problems in older people than they do in younger adults.

Other medicinesÃ¢â�¬â€�Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking a penicillin, it is especially important that your health care professional know if you are taking any of the following:

Valproic acid (e.g., Depakene)Ã¢â�¬â€�These medicines may increase the chance of liver damage if taken with cloxacillin, dicloxacillin, flucloxacillin, mezlocillin, nafcillin, oxacillin, or piperacillin

Amiloride (e.g., Midamor) or

Benazepril (e.g., Lotensin) or

Captopril (e.g., Capoten) or

Enalapril (e.g., Vasotec) or

Fosinopril (e.g., Monopril) or

Lisinopril (e.g., Prinivil, Zestril) or

Potassium-containing medicine or

Quinapril (e.g., Accupril) or

Ramipril (e.g., Altace) or

Spironolactone (e.g., Aldactone) or

Triamterene (e.g., Dyrenium)Ã¢â�¬â€�Use of these medicines with penicillin G by injection may cause an increase in side effects

Anticoagulants (blood thinners) or

Dipyridamole (e.g., Persantine) or

Divalproex (e.g., Depakote) or

Heparin (e.g., Panheprin) or

Inflammation or pain medicine (except narcotics) or

Pentoxifylline (e.g., Trental) or

Plicamycin (e.g., Mithracin) or

Sulfinpyrazone (e.g., Anturane) or

Valproic acid (e.g., Depakene)Ã¢â�¬â€�Use of these medicines with high doses of carbenicillin, piperacillin, or ticarcillin may increase the chance of bleeding

Chloramphenicol (e.g., Chloromycetin) or

Erythromycins (e.g., E.E.S., E-Mycin, ERYC) or

Sulfonamides (e.g., Gantanol, Gantrisin) or Tetracyclines (e.g., Achromycin, Minocin, Vibramycin)Ã¢â�¬â€�Use of these medicines with penicillins may prevent the penicillin from working properly Cholestyramine (e.g., Questran) or

Colestipol (e.g., Colestid)Ã¢â�¬â€�Use of these medicines with oral penicillin G may prevent penicillin G from working properly

Oral contraceptives (birth control pills) containing estrogenÃ¢â�¬â€�Use of ampicillin, amoxicillin, or penicillin V with estrogen-containing oral contraceptives may prevent oral contraceptives from working properly, increasing the chance of pregnancy

Methotrexate (e.g., Mexate)Ã¢â�¬â€�Use of methotrexate with penicillins may increase the chance of side effects of methotrexate

Probenecid (e.g., Benemid)Ã¢â�¬â€�Probenecid causes penicillins to build up in the blood. This may increase the chance of side effects. However, your doctor may want to give you probenecid with a penicillin to treat some infections

Other medical problemsÃ¢â�¬â€�The presence of other medical problems may affect the use of penicillins. Make sure you tell your doctor if you have any other medical problems, especially:

Allergy, general (such as asthma, eczema, hay fever, hives), history ofÃ¢â�¬â€�Patients with a history of general allergies may be more likely to have a severe reaction to penicillins

Bleeding problems, history ofÃ¢â�¬â€�Patients with a history of bleeding problems may be more likely to have bleeding when receiving carbenicillin, piperacillin, or ticarcillin

Congestive heart failure (CHF) or

High blood pressureÃ¢â�¬â€�Large doses of carbenicillin or ticarcillin may make these conditions worse, because these medicines contain a large amount of salt

Cystic fibrosisÃ¢â�¬â€�Patients with cystic fibrosis may have an increased chance of fever and skin rash when receiving piperacillin

Kidney diseaseÃ¢â�¬â€�Patients with kidney disease may have an increased chance of side effects

Mononucleosis (Ã¢â�¬Å“monoÃ¢â�¬Â�)Ã¢â�¬â€�Patients with mononucleosis may have an increased chance of skin rash when receiving ampicillin, bacampicillin, or pivampicillin

PhenylketonuriaÃ¢â�¬â€�Some strengths of the amoxicillin chewable tablets contain aspartame, which is changed by the body to phenylalanine, a substance that is harmful to patients with phenylketonuria.

Stomach or intestinal disease, history of (especially colitis, including colitis caused by antibiotics)Ã¢â�¬â€�Patients with a history of stomach or intestinal disease may be more likely to develop colitis while taking penicillins

Proper Use of This MedicinePenicillins (except bacampicillin tablets, amoxicillin, penicillin V, pivampicillin, and pivmecillinam) are best taken with a full glass (8 ounces) of water on an empty stomach (either 1 hour before or 2 hours after meals) unless otherwise directed by your doctor.

Amoxicillin, penicillin V, pivampicillin, and pivmecillinam may be taken on a full or empty stomach.

The liquid form of amoxicillin may also be taken by itself or mixed with formulas, milk, fruit juice, water, ginger ale, or other cold drinks. If mixed with other liquids, take immediately after mixing. Be sure to drink all the liquid to get the full dose of medicine.

For patients taking bacampicillin:

The liquid form of this medicine is best taken with a full glass (8 ounces) of water on an empty stomach (either 1 hour before or 2 hours after meals) unless otherwise directed by your doctor.

The tablet form of this medicine may be taken on a full or empty stomach.

For patients taking penicillin G by mouth:

Do not drink acidic fruit juices (for example, orange or grapefruit juice) or other acidic beverages within 1 hour of taking penicillin G since this may keep the medicine from working properly.

For patients taking the oral liquid form of penicillins :

This medicine is to be taken by mouth even if it comes in a dropper bottle. If this medicine does not come in a dropper bottle, use a specially marked measuring spoon or other device to measure each dose accurately. The average household teaspoon may not hold the right amount of liquid.

Do not use after the expiration date on the label. The medicine may not work properly after that date. If you have any questions about this, check with your pharmacist.

For patients taking the chewable tablet form of amoxicillin :

Tablets should be chewed or crushed before they are swallowed.

To help clear up your infection completely, keep taking this medicine for the full time of treatment, even if you begin to feel better after a few days. If you have a Ã¢â�¬Å“strepÃ¢â�¬Â� infection, you should keep taking this medicine for at least 10 days. This is especially important in Ã¢â�¬Å“strepÃ¢â�¬Â� infections. Serious heart problems could develop later if your infection is not cleared up completely. Also, if you stop taking this medicine too soon, your symptoms may return.

This medicine works best when there is a constant amount in the blood or urine. To help keep the amount constant, do not miss any doses. Also, it is best to take the doses at evenly spaced times, day and night. For example, if you are to take four doses a day, the doses should be spaced about 6 hours apart. If this interferes with your sleep or other daily activities, or if you need help in planning the best times to take your medicine, check with your health care professional.

DosingÃ¢â�¬â€�

The dose of these medicines will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of these medicines. If your dose is different, do not change it unless your doctor tells you to do so.

The number of tablets or teaspoonfuls of suspension that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are taking a penicillin.

Adults, teenagers, and children weighing more than 40 kilograms (kg) (88 pounds)Ã¢â�¬â€�250 to 500 milligrams (mg) every eight hours or 500 to 875 mg every twelve hours, depending on the type and severity of the infection.

Neonates and infants up to 3 months of ageÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 15 mg per kg (6.8 mg per pound) of body weight or less every twelve hours.

Infants 3 months of age and older and children weighing up to 40 kg (88 lbs.)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 6.7 to 13.3 mg per kg (3 to 6 mg per pound) of body weight every eight hours or 12.5 to 22.5 mg per kg (5.7 to 10.2 mg per pound) of body weight every twelve hours.

Adults: 1000 mg twice a day every twelve hours for fourteen days, along with the two other medicines, clarithromycin and lansoprazole, as directed by your doctor.

Teenagers and children: Use and dose must be determined by your doctor.

For dual medicine therapyÃ¢â�¬â€�

Adults: 1000 mg three times a day every eight hours for fourteen days, along with the other medicine, lansoprazole, as directed by your doctor.

Teenagers and children: Use and dose must be determined by your doctor.

For ampicillin

For bacterial infections:

For oral dosage forms (capsules and oral suspension):

Adults, teenagers, and children weighing more than 20 kilograms (kg) (44 pounds)Ã¢â�¬â€�250 to 500 milligrams (mg) every six hours.

Infants and children weighing up to 20 kg (44 pounds)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 12.5 to 25 mg per kg (5.7 to 11.4 mg per pound) of body weight every six hours; or 16.7 to 33.3 mg per kg (7.6 to 15 mg per pound) of body weight every eight hours.

For injection dosage form:

Adults, teenagers, and children weighing more than 20 kg (44 pounds)Ã¢â�¬â€�250 to 500 mg, injected into a vein or muscle every three to six hours.

Infants and children weighing up to 20 kg (44 pounds)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 12.5 mg per kg (5.7 mg per pound) of body weight, injected into a vein or muscle every six hours.

For bacampicillin

For bacterial infections:

For oral dosage forms (oral suspension and tablets):

Adults, teenagers, and children weighing more than 25 kilograms (kg) (55 pounds)Ã¢â�¬â€�400 to 800 milligrams (mg) every twelve hours.

Children weighing up to 25 kg (55 pounds)Ã¢â�¬â€�Bacampicillin tablets are not recommended for use in children weighing up to 25 kg (55 pounds). The dose of the oral suspension is based on body weight and must be determined by your doctor. The usual dose is 12.5 to 25 mg per kg (5.7 to 11.4 mg per pound) of body weight every twelve hours.

For carbenicillin

For bacterial infections:

For oral dosage form (tablets):

Adults and teenagersÃ¢â�¬â€�500 milligrams (mg) to 1 gram every six hours.

ChildrenÃ¢â�¬â€�Dose must be determined by your doctor.

For injection dosage form:

Adults and teenagersÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 50 to 83.3 mg per kilogram (kg) (22.8 to 37.9 mg per pound) of body weight, injected into a vein or muscle every four hours.

Older infants and childrenÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 16.7 to 75 mg per kg (7.6 to 34 mg per pound) of body weight, injected into a vein or muscle every four to six hours.

For cloxacillin

For bacterial infections:

For oral dosage form (capsules and oral solution):

Adults, teenagers, and children weighing more than 20 kilograms (kg) (44 pounds)Ã¢â�¬â€�250 to 500 milligrams (mg) every six hours.

Infants and children weighing up to 20 kg (44 pounds)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 6.25 to 12.5 mg per kg (2.8 to 5.7 mg per pound) of body weight every six hours.

For injection dosage form:

Adults, teenagers, and children weighing more than 20 kgÃ¢â�¬â€�250 to 500 mg, injected into a vein every six hours.

Infants and children weighing up to 20 kg (44 pounds)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 6.25 to 12.5 mg per kg (2.8 to 5.7 mg per pound) of body weight, injected into a vein every six hours.

For dicloxacillin

For bacterial infections:

For or oral dosage form (capsules and oral suspension):

Adults, teenagers, and children weighing more than 40 kilograms (kg) (88 pounds)Ã¢â�¬â€�125 to 250 milligrams (mg) every six hours.

Infants and children weighing up to 40 kg (88 pounds)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 3.1 to 6.2 mg per kg (1.4 to 2.8 mg per pound) of body weight every six hours.

For flucloxacillin

For bacterial infections:

For oral dosage form (capsules and oral suspension):

Adults, teenagers, and children more than 12 years of age and weighing more than 40 kilograms (kg) (88 pounds)Ã¢â�¬â€�250 to 500 milligrams (mg) every six hours.

Children less than 12 years of age and weighing up to 40 kg (88 pounds)Ã¢â�¬â€�125 to 250 mg every six hours; or 6.25 to 12.5 mg per kg (2.8 to 5.7 mg per pound) of body weight every six hours.

Infants up to 6 months of ageÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 6.25 mg per kg (2.8 mg per pound) of body weight every six hours.

For methicillin

For bacterial infections:

For injection dosage form:

Adults, teenagers, and children weighing more than 40 kilograms (kg) (88 pounds)Ã¢â�¬â€�1 gram injected into a muscle every four to six hours; or 1 gram injected into a vein every six hours.

Children weighing up to 40 kg (88 pounds)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 25 milligrams (mg) per kg (11.4 mg per pound) of body weight, injected into a vein or muscle every six hours.

For mezlocillin

For bacterial infections:

For injection dosage form:

Adults and teenagersÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 33.3 to 87.5 milligrams (mg) per kilogram (kg) (15.1 to 39.8 mg per pound) of body weight, injected into a vein or muscle every four to six hours; or 3 to 4 grams every four to six hours.

Infants over 1 month of age and children up to 12 years of ageÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 50 mg per kg (22.7 mg per pound) of body weight, injected into a vein or muscle every four hours.

For nafcillin

For bacterial infections:

For oral dosage form (capsules and tablets):

Adults and teenagersÃ¢â�¬â€�250 milligrams (mg) to 1 gram every four to six hours.

Older infants and childrenÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 6.25 to 12.5 mg per kilogram (kg) (2.8 to 5.7 mg per pound) of body weight every six hours.

NewbornsÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 10 mg per kg (4.5 mg per pound) of body weight every six to eight hours.

For injection dosage form:

Adults and teenagersÃ¢â�¬â€�500 mg to 2 grams injected into a vein or muscle every four to six hours.

Infants and childrenÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 10 to 25 mg per kg (4.5 to 11.4 mg per pound) of body weight, injected into a muscle every twelve hours; or 10 to 40 mg per kg (4.5 to 18.2 mg per pound) of body weight, injected into a vein every four to eight hours.

For oxacillin

For bacterial infections:

For oral dosage form (capsules and oral solution):

Adults, teenagers, and children weighing more than 40 kilograms (kg) (88 pounds)Ã¢â�¬â€�500 milligrams (mg) to 1 gram every four to six hours.

Children weighing up to 40 kg (88 pounds)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 12.5 to 25 mg per kg (5.7 to 11.4 mg per pound) of body weight every six hours.

For injection dosage form:

Adults, teenagers, and children weighing more than 40 kg (88 pounds)Ã¢â�¬â€�250 mg to 1 gram injected into a vein or muscle every four to six hours.

Children weighing up to 40 kg (88 pounds)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 12.5 to 25 mg per kg (5.7 to 11.4 mg per pound) of body weight, injected into a vein or muscle every four to six hours.

Premature infants and newbornsÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 6.25 mg per kg (2.8 mg per pound) of body weight, injected into a vein or muscle every six hours.

For penicillin G

For bacterial infections:

For oral dosage form (oral solution, oral suspension, and tablets):

Adults and teenagersÃ¢â�¬â€�200,000 to 500,000 Units (125 to 312 milligrams [mg]) every four to six hours.

Infants and children less than 12 years of ageÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 4167 to 30,000 Units per kilogram (kg) (189 to 13,636 Units per pound) of body weight every four to eight hours.

For benzathine injection dosage form:

Adults and teenagersÃ¢â�¬â€�1,200,000 to 2,400,000 Units injected into a muscle as a single dose.

Infants and childrenÃ¢â�¬â€�300,000 to 1,200,000 Units injected into a muscle as a single dose; or 50,000 Units per kg (22,727 Units per pound) of body weight injected into a muscle as a single dose.

For injection dosage forms (potassium and sodium salts):

Adults and teenagersÃ¢â�¬â€�1,000,000 to 5,000,000 Units, injected into a vein or muscle every four to six hours.

Older infants and childrenÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 8333 to 25,000 Units per kg (3788 to 11,363 Units per pound) of body weight, injected into a vein or muscle every four to six hours.

Premature infants and newbornsÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 30,000 Units per kg (13,636 Units per pound) of body weight, injected into a vein or muscle every twelve hours.

For procaine injection dosage form:

Adults and teenagersÃ¢â�¬â€�600,000 to 1,200,000 Units injected into a muscle once a day.

ChildrenÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 50,000 Units per kg (22,727 Units per pound) of body weight, injected into a muscle once a day.

For penicillin V

For bacterial infections:

For the benzathine salt oral dosage form (oral solution):

Adults and teenagersÃ¢â�¬â€�200,000 to 500,000 Units every six to eight hours.

Adults and teenagersÃ¢â�¬â€�125 to 500 milligrams (mg) every six to eight hours.

ChildrenÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 2.5 to 16.7 mg per kilogram (kg) (1.1 to 7.6 mg per pound) of body weight every four to eight hours.

For piperacillin

For bacterial infections:

For injection dosage form:

Adults and teenagersÃ¢â�¬â€�3 to 4 grams, injected into a vein or muscle every four to six hours.

Infants and childrenÃ¢â�¬â€�Dose must be determined by your doctor.

For pivampicillin

For bacterial infections:

For oral dosage form (oral suspension):

Adults, teenagers, and children 10 years of age and olderÃ¢â�¬â€�525 to 1050 milligrams (mg) two times a day.

Children 7 to 10 years of ageÃ¢â�¬â€�350 mg two times a day.

Children 4 to 6 years of ageÃ¢â�¬â€�262.5 mg two times a day.

Children 1 to 3 years of ageÃ¢â�¬â€�175 mg two times a day.

Infants 3 to 12 months of ageÃ¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 20 to 30 mg per kilogram (kg) (9.1 to 13.6 mg per pound) of body weight two times a day.

For oral dosage form (tablets):

Adults, teenagers, and children 10 years of age and olderÃ¢â�¬â€�500 mg to 1 gram two times a day.

Children up to 10 years of ageÃ¢â�¬â€�Dose must be determined by your doctor.

For pivmecillinam

For bacterial infections:

For oral dosage form (tablets):

Adults, teenagers, and children weighing more than 40 kilograms (kg) (88 pounds)Ã¢â�¬â€�200 milligrams (mg) two to four times a day for three days.

Children up to 40 kg (88 pounds)Ã¢â�¬â€�Dose must be determined by your doctor.

For ticarcillin

For bacterial infections:

For injection dosage form:

Adults, teenagers, and children weighing more than 40 kilograms (kg) (88 pounds)Ã¢â�¬â€�3 grams injected into a vein every four hours; or 4 grams injected into a vein every six hours.

Children up to 40 kg (88 pounds)Ã¢â�¬â€�Dose is based on body weight and must be determined by your doctor. The usual dose is 33.3 to 75 milligrams (mg) per kg (15 to 34 mg per pound) of body weight, injected into a vein every four to six hours.

Missed doseÃ¢â�¬â€�

If you miss a dose of this medicine, take it as soon as possible. This will help to keep a constant amount of medicine in the blood or urine. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

StorageÃ¢â�¬â€�

To store this medicine:

Keep out of the reach of children.

Store away from heat and direct light.

Do not store the capsule or tablet form of penicillins in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.

Store the oral liquid form of penicillins in the refrigerator because heat will cause this medicine to break down. However, keep the medicine from freezing. Follow the directions on the label.

Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Precautions While Using This MedicineIf your symptoms do not improve within a few days, or if they become worse, check with your doctor.

Penicillins may cause diarrhea in some patients.

Check with your doctor if severe diarrhea occurs . Severe diarrhea may be a sign of a serious side effect. Do not take any diarrhea medicine without first checking with your doctor . Diarrhea medicines may make your diarrhea worse or make it last longer.

For mild diarrhea, diarrhea medicine containing kaolin or attapulgite (e.g., Kaopectate tablets, Diasorb) may be taken. However, other kinds of diarrhea medicine should not be taken. They may make your diarrhea worse or make it last longer.

If you have any questions about this or if mild diarrhea continues or gets worse, check with your health care professional.

Oral contraceptives (birth control pills) containing estrogen may not work properly if you take them while you are taking ampicillin, amoxicillin, or penicillin V. Unplanned pregnancies may occur. You should use a different or additional means of birth control while you are taking any of these penicillins. If you have any questions about this, check with your health care professional.

For diabetic patients:

Penicillins may cause false test results with some urine sugar tests. Check with your doctor before changing your diet or the dosage of your diabetes medicine.

Before you have any medical tests, tell the doctor in charge that you are taking this medicine. The results of some tests may be affected by this medicine.

Side Effects of This MedicineAlong with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Stop taking this medicine and get emergency help immediately if any of the following side effects occur:

In addition to the side effects mentioned above, check with your doctor immediately if any of the following side effects occur:

Rare

Abdominal or stomach cramps and pain (severe); abdominal tenderness; convulsions (seizures); decreased amount of urine; diarrhea (watery and severe), which may also be bloody; mental depression; nausea and vomiting; pain at place of injection; sore throat and fever ; unusual bleeding or bruising; yellow eyes or skin

Some of the above side effects (severe abdominal or stomach cramps and pain, and watery and severe diarrhea, which may also be bloody) may also occur up to several weeks after you stop taking any of these medicines.

Rare--For penicillin G procaine only

Agitation or combativeness; anxiety ; confusion; fear of impending death; feeling, hearing, or seeing things that are not real

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

More common

Diarrhea (mild); headache; sore mouth or tongue; vaginal itching and discharge; white patches in the mouth and/or on the tongue

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Additional Information

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, penicillins are used in certain patients with the following medical conditions: